Selective extraction of Fe3+ by a polymeric calix[4]arene

A polymeric compound containing more than one calixarene molecule was synthesized by reacting the oligomer (2) with 25,26,27‐tribenzoyloxy‐28‐hydroxy calix[4]arene. After basic hydrolysis of 3a, the polymeric calixarene (3b) was utilized for selective extraction of some metal cations from aqueous phase to organic phase. It was found that the compound (3b) was selective toward Fe3+ from an aqueous solution containing Cu2+, Ni2+, Co2+ and Fe3+ cations. The mechanism of the extraction process was discussed. © 1994 John Wiley & Sons, Inc. Copyright © 1994 John Wiley & Sons, Inc.